The tweens have prowled the Kremlin in trench coats, roamed a Harry Potter movie set in London, and studied slave history in Africa as they racked up tens of thousands of miles crisscrossing the Atlantic Ocean, time zones and international borders with their parents this summer.

Stateside, 11-year-old Malia and 8-year-old Sasha explored the American West on a family tour of Yellowstone National Park and the Grand Canyon. They went whitewater rafting in the rain and hail in Montana, watched Old Faithful shoot steam skyward, and spent time picking peaches in Colorado.

Summer ended with a week at a secluded estate on Martha's Vineyard in Massachusetts, where the girls dug their toes in the sand at the beach, rode bikes and hung out at an arcade, followed by a final getaway to the presidential retreat at Camp David, Md.

And they weren't exactly stuck riding coach for all their farflung travels. If only Air Force One gave out frequent flier miles.

The lazy days of summer between the girls' trips included watching Fourth of July fireworks from the White House balcony, sleepovers inside and playtime on the lawn with the furry Portuguese Water Dog they named Bo.

Through it all, first mom Michelle Obama tried to keep the girls well grounded.

"We've instituted Camp Obama in my house, which means that the television and the computers are off all day until after dinner and right before bedtime," Mrs. Obama said a few days before the girls' summer vacation began in June.

But the White House is anything but a typical summer camp.

As soon as the girls' classes at Sidwell Friends School ended, Sasha and Malia joined Mrs. Obama for a Paris rendezvous with dad, who had been in the Middle East and Europe. The president headed back to Washington after a few days, but Michelle and the girls lingered, spending a few more days in Paris and London, part 8th birthday celebration for Sasha.

In Paris, they toured the Eiffel Tower, Notre Dame and the Louvre and Pompidou Center museums. They ate lunch at the Elysee presidential palace with French President Nicolas Sarkozy and his wife, Carla. They shopped at Bonpoint, a high-end children's store.

London brought visits to Big Ben, the British Parliament's famous clock tower, as well as to Westminster Abbey, the Tower of London, a Harry Potter movie set and Buckingham Palace, where they got a tour and a greeting from Queen Elizabeth II. They also took in "The Lion King" musical.

The family set out on another trip right after Malia turned 11 on July 4 that took them to Moscow, Rome and Ghana — all in one week.

At the Kremlin, Sasha stuffed her hands into her pockets as she walked its hallways. President Barack Obama said they began calling her Agent 99, after a character in the 1960s TV spy comedy "Get Smart."

"I thought she was going to pull out her shoe phone," the president joked.

A highlight of the visit to Rome was the Obama family's meeting with the pope. The sisters also took in such ancient Roman archaeological wonders as the Colosseum and the Pantheon, a domed monument in the city center. The also had fun learning how to make blackberry and banana gelato at Giolitti, the Italian capital's most famous ice cream parlor, and left the shop with several pounds of the ice cold confection.

The trips weren't all carefree and full of fun, however. There were sober moments, too, and lessons to be learned.

After touring Cape Coast Castle in Accra, Ghana, a holding cell for Africans shipped into slavery, Obama said he hoped that seeing the former slave fortress would help his daughters, "who are growing up in such a blessed way," to understand their obligation to fight oppression and cruelty.

Fun and serious, overseas and closer to home, summer travels have given Sasha and Malia a window on the world that opens to few youngsters.

"Their eyes and ears and their hearts and minds are open to people all over the world and to the experiences of other people all over the world and to other cultures and that will serve them well for the rest of their lives," said Anita McBride, chief of staff to Laura Bush in the second term.

There's a long history of White House children tagging along with their globe-trotting parents.

Susan Ford went to China with her father. Chelsea Clinton traveled to Asia and Africa with her mother, Hillary Rodham Clinton, now the secretary of state. Bush twins Barbara and Jenna accompanied their parents on multiple visits to Africa.

While taking such trips might not be how the average 11- or 8-year-old would choose to spend the summer, McBride thinks the Obamas recognize their stay in the White House is limited, and they want to share the experience with their children.

"For the president, it's going to be over real quick," said Doug Wead, who interviewed presidential kids for his book, "All the President's Children."

Malia, now a sixth-grader, and Sasha, a second-grader, did plenty of close-to-home fun stuff this summer, too, as did lots of other children whose families, because of the economy, don't have the money to get away on vacation this year

They've had sleepovers with friends at both the White House and Camp David. They were among screaming fans at concerts by Beyonce and the Jonas Brothers. They also waited in line like any other D.C. tourists at Madame Tussauds museum, where they giggled at the wax replicas of their parents.

After all that, one question remains. What's left to do next summer?